A federal appeals court in San Francisco will consider a lawsuit Thursday alleging that a California high school violated students’ free speech when they were not allowed to wear American flag t-shirts on Cinco de Mayo.

The suit stems from May 5, 2010, when three students wearing American flag t-shirts arrived at Live Oak High School in Morgan Hill, Calif., a town south of San Jose. Cinco de Mayo is often observed as a celebration of Mexican heritage, and other students warned administrators of possible trouble. The students wearing the flags were ordered to turn their shirts inside-out or to go home. They went home, and later filed a lawsuit alleging a violation of their free speech rights, the Associated Press reports.

In December 2011, a lower court tossed out the students’ lawsuit, ruling that school administrators have wide latitude to ensure the safety of their students.